• Associations and predictive power of dietary patterns on metabolic syndrome and its components 

      Moe, Åse Mari; Ytterstad, Elinor; Hopstock, Laila Arnesdatter; Løvsletten, Ola; Carlsen, Monica Hauger; Sørbye, Sigrunn Holbek (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-31)
      Background and aims: Metabolic syndrome (MetS) defines important risk factors in the development of cardiovascular diseases and other serious health conditions. This study aims to investigate the influence of different dietary patterns on MetS and its components, examining both associations and predictive performance.<p> <p>Methods and results: The study sample included 10,750 participants from ...
    • Bayesian Computing with INLA: A Review 

      Rue, Håvard; Riebler, Andrea Ingeborg; Sørbye, Sigrunn Holbek; Illian, Janine B.; Simpson, Daniel Peter; Lindgren, Finn Kristian (Journal article; Tidsskriftartikkel, 2016-12-23)
      The key operation in Bayesian inference is to compute high-dimensional integrals. An old approximate technique is the Laplace method or approximation, which dates back to Pierre-Simon Laplace (1774). This simple idea approximates the integrand with a second-order Taylor expansion around the mode and computes the integral analytically. By developing a nested version of this classical idea, combined ...
    • Estimation of Excess Mortality and Years of Life Lost to COVID-19 in Norway and Sweden between March and November 2020 

      Rypdal, Martin Wibe; Rypdal, Kristoffer; Løvsletten, Ola; Sørbye, Sigrunn Holbek; Ytterstad, Elinor; Bianchi, Filippo Maria (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-08)
      We estimate the weekly excess all-cause mortality in Norway and Sweden, the years of life lost (YLL) attributed to COVID-19 in Sweden, and the significance of mortality displacement. We computed the expected mortality by taking into account the declining trend and the seasonality in mortality in the two countries over the past 20 years. From the excess mortality in Sweden in 2019/20, we estimated ...
    • Finite-sample properties of estimators for first and second order autoregressive processes 

      Sørbye, Sigrunn Holbek; Nicolau, Pedro Guilherme; Rue, Håvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-12-05)
      The class of autoregressive (AR) processes is extensively used to model temporal dependence in observed time series. Such models are easily available and routinely fitted using freely available statistical software like R. A potential problem is that commonly applied estimators for the coefficients of AR processes are severely biased when the time series are short. This paper studies the ...
    • Fractional Gaussian noise: Prior specification and model comparison 

      Sørbye, Sigrunn Holbek; Rue, Håvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-07)
      Fractional Gaussian noise (fGn) is a stationary stochastic process used to model anti-persistent or persistent dependency structures in observed time series. Properties of the autocovariance function of fGn are characterised by the Hurst exponent (<i>H)</i>, which in Bayesian contexts typically has been assigned a uniform prior on the unit interval. This paper argues why a uniform prior is ...
    • Identifying dietary patterns across age, educational level and physical activity level in a cross-sectional study: the Tromsø Study 2015 - 2016 

      Moe, Åse Mari; Sørbye, Sigrunn Holbek; Hopstock, Laila Arnesdatter; Carlsen, Monica Hauger; Løvsletten, Ola; Ytterstad, Elinor (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-15)
      <p><b>Background</b> A healthy diet can decrease the risk of several lifestyle diseases. From studying the health effects of single foods, research now focuses on examining complete diets and dietary patterns reflecting the combined intake of different foods. The main goals of the current study were to identify dietary patterns and then investigate how these differ in terms of sex, age, educational ...
    • Incorporating capture heterogeneity in the estimation of autoregressive coefficients of animal population dynamics using capture–recapture data 

      Nicolau, Pedro Guilherme; Sørbye, Sigrunn Holbek; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-31)
      Population dynamic models combine density dependence and environmental effects. Ignoring sampling uncertainty might lead to biased estimation of the strength of density dependence. This is typically addressed using state‐space model approaches, which integrate sampling error and population process estimates. Such models seldom include an explicit link between the sampling procedures and the true ...
    • Modeling Solar Orbiter dust detection rates in the inner heliosphere as a Poisson process 

      Kociscak, Samuel; Kvammen, Andreas; Mann, Ingrid; Sørbye, Sigrunn Holbek; Theodorsen, Audun; Zaslavsky, Arnaud (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-20)
      Context. Solar Orbiter provides dust detection capability in the inner heliosphere, but estimating physical properties of detected dust from the collected data is far from straightforward.<p> <p>Aims. First, a physical model for dust collection considering a Poisson process is formulated. Second, it is shown that dust on hyperbolic orbits is responsible for the majority of dust detections with ...
    • Norwegian Open Fracture Management System: Outcomes after 10 Years Working in Low-Resource Settings in Cambodian Hospitals 

      Tajsic, Nenad; Sørbye, Sigrunn Holbek; Nguon, Sophy; Sokh, Vannara; Lim, Aymeric (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-13)
      Introduction: The treatment of open lower limb fractures represents a major challenge for any trauma surgeon, and this even more so in resource-limited areas. The aim of the study is to describe the intervention, report the treatment plan, and observe the effectiveness of the Norwegian Open Fracture Management System in saving lower limbs in rural settings.<p> <p>Materials and Methods: A ...
    • Ocean migration of pop-up satellite archival tagged Atlantic salmon from the Miramichi River in Canada 

      Strøm, John Fredrik; Thorstad, Eva Bonsak; Chafe, Graham; Sørbye, Sigrunn Holbek; Righton, David; Rikardsen, Audun H.; Carr, Jonathan (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-01-13)
      The ocean migration of 16 post-spawned adult Atlantic salmon [Salmo salar L.] from the Miramichi River, Canada, tagged concurrently with pop-up satellite archival tags and acoustic transmitters was reconstructed using a Hidden Markov Model. Individuals exclusively utilized areas within the Gulf of St Lawrence and the Labrador Sea, and showed little overlap with known distributions of European stocks. ...
    • Penalised Complexity Priors for Stationary Autoregressive Processes 

      Sørbye, Sigrunn Holbek; Rue, Håvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-05-23)
      The autoregressive (AR) process of order p(AR(p)) is a central model in time series analysis. A Bayesian approach requires the user to define a prior distribution for the coefficients of the AR(p) model. Although it is easy to write down some prior, it is not at all obvious how to understand and interpret the prior distribution, to ensure that it behaves according to the users' prior knowledge. In ...
    • Penalising Model Component Complexity: A Principled, Practical Approach to Constructing Priors 

      Simpson, Daniel; Rue, Håvard; Riebler, Andrea Ingeborg; Martins, Thiago Guerrera; Sørbye, Sigrunn Holbek (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-06)
      In this paper, we introduce a new concept for constructing prior distributions. We exploit the natural nested structure inherent to many model components, which defines the model component to be a flexible extension of a base model. Proper priors are defined to penalise the complexity induced by deviating from the simpler base model and are formulated after the input of a user-defined scaling parameter ...
    • Seafood production in Northern Norway: Analyzing variation and co-development in aquaculture and coastal fisheries 

      Espinasse, Marina; Mikkelsen, Eirik Inge; Sørbye, Sigrunn Holbek; Skern-Mauritzen, Mette; Falk-Andersson, Jannike; Fauchald, Per (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-27)
      Norway is one of the leading ocean-based food production nations. Its seafood industry comprises wild-capture fisheries and farmed fish production. Both industries play a provisional role but also contribute to economic development of the country and help sustain coastal communities, particularly, in Northern Norway. Coastal fishery has been the staple industry in Northern Norway for centuries, while ...
    • Seasonality, density dependence, and spatial population synchrony 

      Antunes Lopes Da Silva Nicolau, Pedro Guilherme; Ims, Rolf Anker; Sørbye, Sigrunn Holbek; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-15)
      Studies of spatial population synchrony constitute a central approach for understanding the drivers of ecological dynamics. Recently, identifying the ecological impacts of climate change has emerged as a new important focus in population synchrony studies. However, while it is well known that climatic seasonality and sequential density dependence influences local population dynamics, the role of ...
    • Spatial trend analysis of gridded temperature data at varying spatial scales 

      Haug, Ola; Thorarinsdottir, Thordis Linda; Sørbye, Sigrunn Holbek; Franzke, Christian L.E. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-28)
      Classical assessments of trends in gridded temperature data perform independent evaluations across the grid, thus, ignoring spatial correlations in the trend estimates. In particular, this affects assessments of trend significance as evaluation of the collective significance of individual tests is commonly neglected. In this article we build a space–time hierarchical Bayesian model for temperature ...
    • Statistical estimation of global surface temperature response to forcing under the assumption of temporal scaling 

      Myrvoll-Nilsen, Eirik; Sørbye, Sigrunn Holbek; Fredriksen, Hege-Beate; Rue, Håvard; Rypdal, Martin Wibe (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-08)
      Reliable quantification of the global mean surface temperature (GMST) response to radiative forcing is essential for assessing the risk of dangerous anthropogenic climate change. We present the statistical foundations for an observation-based approach using a stochastic linear response model that is consistent with the long-range temporal dependence observed in global temperature variability. We ...
    • A toolbox for fitting complex spatial point process models using integrated nested Laplace approximation (INLA) 

      Illian, Janine; Sørbye, Sigrunn Holbek; Rue, Håvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      This paper develops methodology that provides a toolbox for routinely fitting complex models to realistic spatial point pattern data. We consider models that are based on log-Gaussian Cox processes and include local interaction in these by considering constructed covariates. This enables us to use integrated nested Laplace approximation and to considerably speed up the inferential task. In addition, ...
    • Using camera traps to monitor cyclic vole populations 

      Kleiven, Eivind Flittie; Antunes Lopes Da Silva Nicolau, Pedro Guilherme; Sørbye, Sigrunn Holbek; Aars, Jon; Yoccoz, Nigel; Ims, Rolf Anker (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-02)
      Camera traps have become popular labor-efficient and non-invasive tools to study animal populations. The use of camera trap methods has largely focused on large animals and/or animals with identifiable features, with less attention being paid to small mammals, including rodents. Here we investigate the suitability of camera-trap-based abundance indices to monitor population dynamics in two species ...
    • Warming trends and long-range dependent climate variability since year 1900: A Bayesian approach 

      Myrvoll-Nilsen, Eirik; Fredriksen, Hege-Beate; Sørbye, Sigrunn Holbek; Rypdal, Martin wibe (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-21)
      Temporal persistence in unforced climate variability makes detection of trends in surface temperature difficult. Part of the challenge is methodological since standard techniques assume a separation of time scales between trend and noise. In this work we present a novel Bayesian approach to trend detection under the assumption of long-range dependent natural variability, and we use estimates of ...
    • You Just Keep on Pushing My Love over the Borderline: A Rejoinder 

      Simpson, Daniel; Rue, Håvard; Riebler, Andrea Ingeborg; Martins, Thiago Guerrera; Sørbye, Sigrunn Holbek (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-06)
      <i>INTRODUCTION</i>: The point of departure for our paper is that most modern statistical models are built to be flexible enough to model diverse data generating mechanisms. Good statistical practice requires us to limit this flexibility, which is typically controlled by a small number of parameters, to the amount “needed” to model the data at hand. The Bayesian framework provides a natural method ...